break apt-get update into its own command, because global state variables
won't work right now; they don't get reset between cooks. need to come
up with a better way to do global variables like that. probably would
have to make some global object that gets reset between cooks and just
assign to keys of it. but i don't really need to go that far, right now.
i'd probably sooner create .dotfiles on the remote machine to track
state since those are persistent between processes.